In news@nature, more on whether experiments in virtual worlds can bypass ethical concerns in physchological tests.
Half the volunteers could see the woman and half could not, communicating with her only through text. Both were told to give her ‘electric shocks’ of increasing voltage when she gave incorrect answers to test questions. The woman responded to these with protests and discomfort, asking for the test to stop as the voltage was ramped up.
The group from whom the virtual woman was hidden delivered shocks up to the maximum voltage, like many of those in Milgram’s experiment. Those who could see her were more likely to stop before reaching this limit2.
Almost half of those who could see the woman said afterwards that they had considered withdrawing from the study, and several actually did. “Of course, consciously everybody knows nothing is happening,” says Slater. “But some parts of the person’s perceptual system just takes it as real. Some part of the brain doesn’t know about virtual reality.”
And instead of becoming accustomed to the virtual person and ceasing to empathise, many volunteers became more anxious as the study continued.